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help memory

i do not know how to get started. If you give me hit how to start this project
i would prciated.

There is three things:

class MemoryManger{

public int allocate () {}

public int deallocate () {}

public void printMemroyState() {}
}

where should be my main

Memory Management
The goal of this lab is to write a simple memory manager based on the topics
covered in class. This lab has two parts.
Write a memory manager that supports contiguous memory allocation. Implement
both first-fit and best-fit policies in your memory manager. For simplicity,
assume that processes do not grow or shrink, and that no compaction is performed
by the memory manager. You should consider the following issues while designing
your memory manager:

Efficiency of your search algorithms: Both first-fit and best-fit will require
you to search for an appropriate hole to accommodate the new process. You
should pay careful attention to your data structures and search algorithms.
For instance, keeping the list of holes sorted by size and using binary search
to search for a hole might improve efficiency of your best-fit algorithms.
We do not require you to use a specific algorithm/data structure to implement
best-fit and first-fit; you have the flexibility of using any search algorithm/data
structure that is efficient. We'll give you 20 points for any design that
is more efficient that a brute-force linear search through an unsorted list
of holes. Similarly, use an efficient search algorithm when deallocating
a process from the processList. Explain all design decisions, the data structures
and search algorithms used clearly in the README file.

Free block coalescing: When a process terminates, the memory allocated to
that process is returned to the list of holes. You should take care to combine
(coalesce) holes that are adjacent to each other and form an larger contiguous
hole. This will reduce the degree of fragmentation incurred by your memory
manager

Implement compaction in your memory manager. It is sufficient to implement
compaction for the best-fit policy. Your memory manager should compact memory
every time it sees external fragmentation (this will occur when a new process
asks for memory and your memory manager is unable to allocate it due to fragmentation).
A simple compaction policy that moves all currently running processes to
the start of main memory and creating one hole at the high region of memory
will get you full credit.

Getting Started
this assignment does not require you to use any special features of Java.
Use the following template as a starting point:

class MemoryManager
{

public MemoryManager(int bytes, int policy)
{ // intialize memory with these many bytes.
// Use first-fit if policy==0, best-fit if policy ==1

}

public int allocate(int bytes, int pid)
{ // allocate these many bytes to the process with this id
// assume that each pid is unique to a process
// return 1 if successful
// return -1 if unsuccessful; print an error indicating
// whether there wasn't sufficient memory or whether
// there you ran into external fragmentation

Data structures
Your memory manager class should maintain two lists: a holeList and a processList
The holeList is a list of holes, with the start location and size of each
hole. The processList is the list of currently active process containing
the process Id, the start location and size of each process. You are free
to use any data structures (arrays, linked list, doubly linked list, etc)
to implement these lists. This decision will also affect the use of search
algorithms to search through these lists.
Input file
You program should take input from a input file and perform actions specified
in the file, while printing out the result of each action. The format of
the input file is as follows:

memorySize policy //initialize memory to this size and use this policy
A size pid // allocate so much memory to this process
D pid // deallocate memory for this process
P // print current state of memory